The synthetic form of a chromatin binding peptide derived from soy, named lunasin, has been discovered to prevent the transformation of normal cells to cancerous foci induced by chemical carcinogens and viral oncogenes. Lunasin has the potential to be a general cancer preventative and could explain epidemiological associations between soy consumption and reduced cancer incidence. Lunasin is found in the water soluble fractions of soy protein preparations and can be extracted by standard purification methods, making it cheaper to commercially produce than chemical synthesis or recombinant DNA. The objective of the proposed research is to extract soy protein fractions that contain biologically active levels of lunasin and use them to develop cancer preventive products. This can be accomplished by first, extracting and purifying lunasin at increasing levels from soy protein preparations, then testing the lunasin-containing fractions in cell transformation assays using chemical carcinogens and viral oncogenes as cancer inducing agents. The most effective lunasin-enriched soy fraction will then be encapsulated in a liposome-based dermal formulation and used in a mice skin cancer study to determine in vivo efficacy in preventing skin tumor formation. Once efficacy of the lunasin topical formulation is determined, pre-clinical and clinical testing for safety and efficacy in preventing skin cancer formation and progression will commence as part of a SBIR Phase Il study. This will eventually lead to the development of lunasin-based topical products such as skin creams, lotions and sunscreen against skin cancer. With approximately one million cases of skin cancer being diagnosed each year and with the aging demographics of the baby boom generation, these chemopreventive products should have a market potential of more than 100 million customers by the year 2003. The proposed research also lays the groundwork for the development of lunasin-based chemopreventive products against other common cancers.